Where are each of the 4 macromolecules found in a cell? 

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The four types of macromolecules in biology are: lipids, carbohydrates, proteins and nucleic acids.

There are two types of nucleic acids: DNA and RNA. In the case of eukaryotic cells, during the majority of the cell cycle, DNA is located in the nucleus. RNA is located in the nucleus and the cytoplasm. In the case of prokaryotic cells, DNA and RNA are both located in the cytoplasm (because there is no nucleus). 

Proteins are located in many parts of the cell. Proteins are found suspended in the cytoplasm, in the various organelle membranes as receptors and channels, and even inside the nucleus (histones). Ribosomes and the cytoskeleton are also made of protein.

Carbohydrates are found as simple sugars dissolved in the intracellular fluid and can also be attached to various protein receptors present in the cell membrane. In plants, cellulose is a carbohydrate that is an important structural component of the cell. 

Lipids are present in membranes. Both the membranes of organelles and the cell membrane itself are composed of lipids. In adipose (fat) cells used for energy storage, lipids are present as fat reservoirs.

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